Time-resolved immunofluorometric assay of human prostate-specific antigen

Area of Science:

• Biochemistry
• Immunology
• Oncology

Background:

• Prostate-specific antigen (PSA) is crucial for prostate cancer diagnosis and monitoring.
• Existing assays may have limitations in convenience, cost, or accuracy.

Purpose of the Study:

• To develop and validate a time-resolved immunofluorometric assay for human serum PSA.
• To assess the assay's performance and compare it with established methods.

Main Methods:

• Utilized strip-wells coated with polyclonal anti-PSA antibodies.
• Developed a PSA label using monoclonal antibodies derivatized with diethylenetriaminepentaacetic acid (DTPA) for Europium (Eu) chelation.
• Quantified PSA using time-resolved immunofluorometry.

Main Results:

• Achieved a minimum detectable PSA concentration of 0.12 microgram/L.
• Demonstrated low PSA levels (<0.2 microgram/L) in most women.
• Observed elevated PSA in older asymptomatic men, potentially indicating "occult" prostatic hyperplasia.
• Showed higher PSA concentrations in patients with prostatic hyperplasia or cancer compared to healthy controls.

Conclusions:

• The developed assay is sensitive, specific, and reliable for human serum PSA measurement.
• The method offers a convenient, inexpensive, and clinically compatible alternative to radioactive assays.
• This assay can aid in the diagnosis and follow-up of prostate conditions.